UniversallyUniqueIdentifier.java
/*
* GovWay - A customizable API Gateway
* https://govway.org
*
* Copyright (c) 2005-2024 Link.it srl (https://link.it).
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 3, as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
package org.openspcoop2.utils.id;
import java.util.UUID;
/**
* UniversallyUniqueIdentifier
*
* @author Poli Andrea (apoli@link.it)
* @author $Author$
* @version $Rev$, $Date$
*/
public class UniversallyUniqueIdentifier implements IUniqueIdentifier {
// There are two different ways of generating a UUID.
//
// If you just need a unique ID, you want a version 1 or version 4.
//
// Version 1: This generates a unique ID based on a network card MAC address and a timer. These IDs are easy to predict (given one, I might be able to guess another one) and can be traced back to your network card. It's not recommended to create these.
//
// Version 4: These are generated from random (or pseudo-random) numbers. If you just need to generate a UUID, this is probably what you want.
//
// UUIDv1 is NOT secure. It isn't meant to be. It is meant to be UNIQUE, not un-guessable. UUIDv1 uses the current timestamp, plus a machine identifier,
// plus some random-ish stuff to make a number that will never be generated by that algorithm again.
// This is appropriate for a transaction ID (even if everyone is doing millions of transactions/s).
// UUIDv4 from reading RFC4122, it looks like that version does NOT eliminate possibility of collisions.
// It is just a random number generator. If that is true, than you have a very GOOD chance of two machines in the world eventually creating the same "UUID"v4
// (quotes because there isn't a mechanism for guaranteeing U.niversal U.niqueness).
// In that situation, I don't think that algorithm belongs in a RFC describing methods for generating unique values. It would belong in a RFC about generating randomness.
// For a set of random numbers:
//
// Riassunto:
//
// Version 1 is based on MAC address and current time ("space and time"). Much less likely to have collisions than Version 4.
//
// Version 4 is based on entirely being generated from random numbers using a cryptographically strong random generator.
//
// The Oracle JVM does not provide a Version 1 generator, apparently because of security and privacy concerns.
// The JVM does not provide access to the MAC address of host machine.
/**
*
*/
private static final long serialVersionUID = 1L;
private UUID uuid;
public UUID getUuid() {
return this.uuid;
}
public void setUuid(UUID uuid) {
this.uuid = uuid;
}
@Override
public String getAsString() {
return this.uuid.toString();
}
@Override
public String toString(){
return this.getAsString();
}
}